So I'm always coming up with random themes like "only characters in hats, sat down" etc.

The latest is to build a team based on CoX (City of Heroes/Villains) archetypes (AT); but not the CoX pieces themselves.

My teams must have at least one of each AT and I'm going a little more
traditional to begin with, where the teams can only have the traditional AT's un-including epics i.e. Khelds & Arachnos.

What pieces would you play or suggest?

It's been a while since I played CoX, so forgive me if my summary of the AT isn't 100% accurate.

Let's list the AT's and see how we get on:

Originally 'heroic':
Blaster - ranged combatants and supporting powers
Controllers - control powers e.g. mind control, forcefields
Defenders - support characters, often buffers that boost or hinder
Scrappers - high dmg close combat
Tankers - can take a load hits and draw/taunt enemies to them but can dish some dmg.

Originally 'villainous':
Brute - Can dish the damage and take a lot of the flak for their team
Corruptor - ranged combatant with buff/debuff
Dominator - crowd control and buff/hinderance
Mastermind - primary is to draw up to 6 minions, secondary set was their own powers like Traps or dark magic/energy etc.
Stalker - stealthed attackers for close combat

Some examples of pieces that may fit the bill.

Elektra from DP set fit the Stalker role perfectly. She can sneak up on pieces and dole some nasty damage, they'll never see it coming.

Blob GSX and Doomsday make good brutes or tankers as they can draw folks to them and take the hits while handing out some of their own.

Now I know my earlier post is heroic vs villainous but as an example, Nick Fury SI is 100pts and I can put 100pts of SHIELD with him at varying point costs to reflect the tiers of minions you'd get as a Mastermind. e.g. x3 ten pt pieces for tier one, x2 twenty pt characters for tier two and x1 thirty pt piece to represent the third tier character.

Vertigo is probably my go to character for a Dominator purely because she has some great crowd control and had the 'secondary' power to 'buff/debuff' with Perplex.

I'm struggling with suitable Defenders.

Controllers obviously allow for MC but if thinking about the powersets from the game, force fields etc allow for Invisible Woman and Magneto, in fact astral creating Doc Strange would be perfect for Illusion Controller.